r330759 - Improve -Warray-bounds to handle multiple array extents rather than only handling the top-most array extent.

[Aaron Ballman via cfe-commits]

Author: aaronballman
Date: Tue Apr 24 12:21:04 2018
New Revision: 330759

URL: http://llvm.org/viewvc/llvm-project?rev=330759&view=rev
Log:
Improve -Warray-bounds to handle multiple array extents rather than only handling the top-most array extent.

Patch by Bevin Hansson.

Modified:
    cfe/trunk/lib/Sema/SemaChecking.cpp
    cfe/trunk/test/SemaCXX/array-bounds.cpp
    cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=330759&r1=330758&r2=330759&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Tue Apr 24 12:21:04 2018
@@ -11277,7 +11277,12 @@ void Sema::CheckArrayAccess(const Expr *
         const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(expr);
         CheckArrayAccess(ASE->getBase(), ASE->getIdx(), ASE,
                          AllowOnePastEnd > 0);
-        return;
+        expr = ASE->getBase();
+        break;
+      }
+      case Stmt::MemberExprClass: {
+        expr = cast<MemberExpr>(expr)->getBase();
+        break;
       }
       case Stmt::OMPArraySectionExprClass: {
         const OMPArraySectionExpr *ASE = cast<OMPArraySectionExpr>(expr);

Modified: cfe/trunk/test/SemaCXX/array-bounds.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/array-bounds.cpp?rev=330759&r1=330758&r2=330759&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/array-bounds.cpp (original)
+++ cfe/trunk/test/SemaCXX/array-bounds.cpp Tue Apr 24 12:21:04 2018
@@ -269,3 +269,18 @@ int test_operator_overload_struct_array_
   struct P x[10] = {0}; // expected-note {{array 'x' declared here}}
   return x[1] + x[11]; // expected-warning {{array index 11 is past the end of the array (which contains 10 elements)}}
 }
+
+int multi[2][2][2]; // expected-note 3 {{array 'multi' declared here}}
+int test_multiarray() {
+  return multi[2][0][0] + // expected-warning {{array index 2 is past the end of the array (which contains 2 elements)}}
+         multi[0][2][0] + // expected-warning {{array index 2 is past the end of the array (which contains 2 elements)}}
+         multi[0][0][2];  // expected-warning {{array index 2 is past the end of the array (which contains 2 elements)}}
+}
+
+struct multi_s {
+  int arr[4];
+};
+struct multi_s multi2[4]; // expected-note {{array 'multi2' declared here}}
+int test_struct_multiarray() {
+  return multi2[4].arr[0]; // expected-warning {{array index 4 is past the end of the array (which contains 4 elements)}}
+}

Modified: cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp?rev=330759&r1=330758&r2=330759&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp (original)
+++ cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp Tue Apr 24 12:21:04 2018
@@ -528,7 +528,7 @@ constexpr int xs6 = p[3]; // expected-er
 constexpr int xs0 = p[-3]; // ok
 constexpr int xs_1 = p[-4]; // expected-error {{constant expression}} expected-note {{cannot refer to element -1}}
 
-constexpr int zs[2][2][2][2] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
+constexpr int zs[2][2][2][2] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; // expected-note {{array 'zs' declared here}}
 static_assert(zs[0][0][0][0] == 1, "");
 static_assert(zs[1][1][1][1] == 16, "");
 static_assert(zs[0][0][0][2] == 3, ""); // expected-error {{constant expression}} expected-note {{read of dereferenced one-past-the-end pointer}}
@@ -536,7 +536,10 @@ static_assert((&zs[0][0][0][2])[-1] == 2
 static_assert(**(**(zs + 1) + 1) == 11, "");
 static_assert(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][-1] + 1) == 11, ""); // expected-error {{constant expression}} expected-note {{cannot refer to element -1 of array of 2 elements in a constant expression}}
 static_assert(*(&(&(*(*&(&zs[2] - 1)[0] + 2 - 2))[2])[-1][2] - 2) == 11, "");
-constexpr int err_zs_1_2_0_0 = zs[1][2][0][0]; // expected-error {{constant expression}} expected-note {{cannot access array element of pointer past the end}}
+constexpr int err_zs_1_2_0_0 = zs[1][2][0][0]; // \
+expected-error {{constant expression}} \
+expected-note {{cannot access array element of pointer past the end}} \
+expected-warning {{array index 2 is past the end of the array (which contains 2 elements)}}
 
 constexpr int fail(const int &p) {
   return (&p)[64]; // expected-note {{cannot refer to element 64 of array of 2 elements}}